CurtPalme.com Home Theater Forum

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Guys

What would you like to see on it? I'd like 7x9 convergence zones, HD10E lenses, silent fans. What would you like to see?

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

A super advanced "Flash ACON" system which uses modern digital camera technology to calculate proper convergence, and execute it, with a precision greater than the human eye can manage. And do it FAST. Use a 36 megapixel sensor for finer than scan line resolution in the ACON system.

Finer convergence steps, optimized for HD and even into UHD territory.

Fully electronic CPC adjustments. 2, 4, and 6 pole. Whatever it takes to yield the best results.

A totally new CLM built with today's technology and with built-in wifi, bluetooth, or both, to allow wireless control of the projector.

Not just ACON, but a complete auto-alignment system that detects the screen boundaries and makes EVERY adjustment necessary (except for mechanical aiming which you still have to do) to get perfect geometry and ideal beam shaping and grey scale calibration as well.

Also, wireless signal transmission. A projector that gets its media directly from your server over your wifi system.

Precision convergence and focus yokes, which hold razor sharp images at high contrast levels.

BANDWIDTH. Aim for 4K.

Elcan manufactured lenses with better specs than any HD10 series lenses you know of.

Higher resolution capable CRTs based on LUGs but with an even finer beam spot size.

The CRTs would use a developed version of the quantum phosphor project that never got off the ground, or, if compatible
with the technology, use quantum dot based phosphors to achieve REC 2020 color coordinates.

Every one of them gets a Vision One style case.

Hey, it's all fantasy. Might as well hang lots of ornaments off it.

Let's add UV and IR channels to it so it's a five tube projector, capable of accurately rendering even
fluorescent colors (day-glow orange, hot pink, etc) with unprecedented fidelity.

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Well

I asked VDC a while back about adding more convergence zones; the response was that a new CLM and new convergence yokes were required for that. There are maybe one or two small shops in Japan/China still making nine inch tubes, but if Nippon Electric Glass is out of the raw tube glass business then supplies of raw glass bulbs will eventually run out; game over.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

Lexel Imaging is still fully capable of making new projection CRTs. I talked to them just a few days ago, seeking technical data on these high res tubes I bought from VDC.

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Okay

Can Lexel make new raw glass? I am told by VDC CEO Ron Ordway that the tolerances on the glass are very finicky.

The other problem is that our perfect Marquee is probably north of $60K at today's prices, and still suffers from sub-300 ANSI lumen output.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

I don't know about if they can make the glass themselves or not. I'd bet, probably not. But if there was demand for a new projector, there would be a large enough order placed to ensure the supply of tubes for it, I'm sure.

If you think tube glass tolerances are finicky, definitely check out this video on how COLOR direct view CRTs are made. The process is absolutely fascinating. Not really all that complex, but the thinking that went into it is fascinating.

http://www.youtube.com/watch?v=Cf-rNlqeWw4

After that one, the link to part 2 is on the right.

NEAT process!

Tim in Phoenix · Joined: 21 Oct 2006 Posts: 4409 Location: Phoenix

Guys

I would also like to see a horizontal board that did not need so much linearity correction. If the scan was 60khz to 152khz that might be easier. Then HT and virtual reality users would all be accommodated.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

I'm trying to understand why adding convergence points would require a different convergence yoke. Maybe it's because adding more convergence points requires a higher rate of dynamic changes in the coil. Thus, a higher convergence frequency, requiring
a lower inductance coil. They'd probably be best off to just use the same magnetics found in Barco 909s in that case. Which I'd recommend anyway. If they didn't go with something really precise and exotic like Syntronics and Discom magnetics.

gjaky · Joined: 05 Jun 2010 Posts: 2802 Location: Budapest, Hungary

gjaky · Joined: 05 Jun 2010 Posts: 2802 Location: Budapest, Hungary

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

Well it's sure above my pay grade and skill level!

But it would be nice, you've got to admit.

While I'm on the subject, what is the difference between "original" ACON and ACON Ultra? I've never known.

I actually don't have any service docs that cover Ultras. Anybody got the Ultra service manual in .pdfs?

Chris

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

9 tubed CRT with 750 ANSI lums and 500 point convergence and zero drift. Mr. Green

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

Well, with the lack of interest on the part of today's youth in going into engineering fields, the day may come when the technological ladder of knowledge may fall due to a lack of anyone who knows how to do something that's essential to supporting the whole ladder.

And then someone will have to bring back the vacuum tube and the picture tube and we'll be back in the CRT business again because nobody has a clue as to how to make a modern TFT or nematic supertwist LCD display with a contrast ratio of 1500:1 or build the proccessors-on-flex-circuits that are critical to making it all work.

Technology is a sensitive thing. SOMEBODY has to know how to design and build and execute EVERY step of the whole ladder.

If just one rung is not occupied, the technology dies until the information is recovered or rediscovered.

draganm · Joined: 08 Mar 2006 Posts: 8990 Location: Colorado

nahhh, today's tech takes plenty of knowledge and todays Electronic engineers have to be just as educated as they ever have, or more so considering software is integral to everything, so you have A-D-A conversion and suck.

What's going to be lost is possible some degree of Analog Circuitry design knowledge, but enough interest in that from hobbyists to keep it alive for a long time too.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

The problem is that if you look at the total picture, the technology ladder is more like a technology family tree, with many diverse skillsets, tools, and other technologies underlying virtually any other.

Just to cite a couple of simple examples, integrated circuits use a photographic process to have their resistive patterns placed on them prior to etching processes. There are a VERY limited number of companies and individuals who are expert at related technologies and processes such as the manufacture of precisely tailored etching chemicals and gases, delivery systems for those chemicals and gases, control systems for the delivery systems, specialized divisions of companies that design and build the photolithography systems, companies that make the photographic resists, master film patterns, etc. and every one of them ultimately is dependent upon a very tiny handful of subject matter experts who are very nearly the sole repositories of such critical knowledge as exactly how to make an epitaxial film emulsion capable of supporting 0.35 nanometer features and how to turn it into a highly consistent deliverable product that is absolutely essential for high density semiconductor manufacturing.

If you follow everything to its originators, along the way you will find many very fragile knowledge and technology links that would be very difficult and time consuming to replace if they should be lost, or get run over by a truck.

xmob135lc · Joined: 15 Sep 2012 Posts: 80

Use a single tube with 1-1 stripe of R-G-B phosphors to project optically overlapped RGB onto a DLP chip and you have geometry for free, and the tube helps with the dithering immensely. Latter probably also nets better result at the pseudo-4k stuff. Probably loose a lot of "dimming zones " because obscene amounts of vertical retrace.

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

But having an RGB projection tube would require it to be three times as large (light output needs) and plus you lose what I consider to be the greatest attribute of 3 CRT projection systems: No spatial displacement of R, G, and B images, when perfectly converged.

3 CRT projection allows red, green, and blue to perfectly overlap. You can't do that in ONE tube.

Imagine the image of a Trinitron or triad dot phosphor direct view CRT, magnified. Frankly it would suck compared to what we have now.

A tube driving a digital device has been done. It was the ILA (LCOS) system used by Hughes-JVC and then by AmPro. But they used three tube systems. One for each color, and the color was derived by dichroic filters in the optical systems in each light path.

An infrared CRT drove a specialized, pixel-less LCD panel with an IR sensitized layer. The layer generated the voltage required to activate the liquid crystals, more or less. Later the idea was turned into D-ILA by removing the CRT and using a high resolution LCD panel.

The basic difference between LCD and D-ILA today is whether you transmit light THROUGH the LCD, or reflect it OFF the LCD.
Or at least that is how I understand it.

xmob135lc · Joined: 15 Sep 2012 Posts: 80

This is no different than 3x LED driving a DMD, I wrote 1-1 stripe per color, not hundreds. The problem is etendue because DMD -s are getting ever smaller with every generation, so older ones would work better. Obviously coupling it to the DMD without apparent color break-up is a challenge.

The smaller surface area can be compensated by successive redraws ( hence I wrote obscene amount of retrace , something like >1000hz vertical, inside 5ms you get >6x redraws, eg. the illuminated area can be >6x smaller and its still plasmaTV levels of motion resolution ).

How this would "suck" , when current high-end LED DLP-s are nothing to sniff at despite the limited native contrast (also LED can't do line/line dimming only subframe, and bad motion resolution).

cmjohnson · Joined: 03 Apr 2006 Posts: 5180 Location: Buried under G90s

It wouldn't be a CRT projector and it would not have the visual characteristics of one. Using a CRT as a light source for a DMD, how would that even work? I'd need to see a few diagrams to understand what you're after.

But to use the CRT as a tricolor illuminator would be very inefficient, and you would lose light output by the truckload. You'd end up with a very dim picture. So you use a DMD...and get a dim picture. That's kind of opposite to the point of DMDs.

I'm trying to understand what you're proposing and how it would be a CRT projector.

xmob135lc · Joined: 15 Sep 2012 Posts: 80

In monitors and tv-s they lost light output because of the shadowmask / aperture grille obstructed the electron beam , just to make the electrons hit the right spot. They researched ways around this was known as the "beam index tube" .

In contrast when you want to direct light onto the DMD , the light can be guided/coupled externally and the image is formed outside (on the mirror device) and no thin stripes or "beam indexing" are needed , just 1x seperate 16:9 phosphor area for every color, so in theory it's nearly the same bright, even with a single electron gun for 3 colors (though that has to be really fast).

This way the CRT is used as a beam adressed LED , since even 64x64 (x3!) partitioned LED can get really messy with electronic adressing and that's not even a whole lot of dimming zones to be justified.On another note I even recall there used to be a DLP projector with bulb in a seperate box and some kind of a hefty tubular connection between the two, seemed rather cool.

http://www.cepro.com/article/projectiondesign_remote_light_source_projectors_with_no_lamps_fans_color_wh

if nothing else, it'd suit rear projection screens, since, it can be hard to position a 80kg CRT for those, but it'd worth it because of screen gain, and it's not like upcoming LED DLP's are geared towards plasma replacement.